They're probably talking about tactical nukes
Basically, strategic nukes are your city killers, tactical nukes are designed to be used against ground troops, armor, forward bases and things like that. They are "less destructive" because you have your own troops operating on the same battlefield, so you want to be somewhat more accurate in controlling their destructive power than you would be if you are throwing strategic nukes around.
Your guys might die of cancer later, but hopefully after they've done their duty for Mother Russia (I doubt Z-man has any tactical nukes).